Yesterday, we took a close look at the AK’s operating group, to enumerate the details that make this pattern such a dependable design. Today, we’re going to be looking at some of the other elements of the AK that make it so reliable, but first I want to clear up some confusion that arose in the comments section of the previous article, regarding what the term “anti-preengagement” refers to. Hopefully the video below will help:

In other words, anti-preengagement is just a mechanism that locks the bolt in the open position with the carrier during cycling, preventing it from rubbing against the receiver and generating friction.

Alright, now on to the rest:

2. Magazine and feedway design

Perhaps the single most critical item in a magazine-fed firearm system is the magazine itself. Without an effective, reliable magazine, a firearm will simply not feed properly, and a common (and essentially correct) estimate is that 95-99% of malfunctions experienced with a modern automatic firearm will be the fault of a bad magazine.

The AR-15 had to claw its way up to an excellent magazine design over decades, but Kalashnikov simply brute-forced the design of the magazines for his AK-47. The Kalashnikov magazine is a hugely overbuilt device that achieves reliability and longevity through sound design and sheer mass combined. Certainly, the Kalashnikov magazine is very well-engineered, but its most distinctive feature is its overbuiltness, especially when considering the original slab-sided pattern,

The original slab-sided magazines, shown here, are an exercise in excess. They are so ludicrously overbuilt that they can be used as hammers regularly and still function. This, perhaps more than anything, is the biggest reason for the AK-47’s reputation as a supremely reliable rifle, especially in peasant hands. Image source: Reader Brandon

The body of AK magazines is a fairly simple curve, but the feed tower is more noteworthy. Overbuilt like the rest of the magazine, the feed tower incorporates clever geometry that supports the magazine when locked in the gun, without requiring an AR-15 style mag well or a chute. Another important feature of the feed tower are the relatively long feed lips, which are long enough to control the round’s travel until its nose has entered the chamber of the barrel. This means that, unlike an AR-15, an AK-47 will be very, very unlikely to have a feeding problem where the round fishtails or yaws and fails to enter the chamber.

Aiding this straight shot to the chamber is the AK’s very clean feedway. Unlike an AR-15, which has to push its rounds over a ramped barrel extension and into the chamber, the AK has virtually nothing in between the round and the chamber itself. Also, the rounds do not have to climb to reach the chamber; the magazine positions them so that they are virtually in-line with it already. This extremely clean feedway design, combined with the feed lip arrangement helps ensure reliable, trouble-free feeding every time. It would be untrue to say that AK’s never had feeding problems, but with the way that the feed lips, feedway, and chamber geometry of the AK are designed, it’s very unlikely!

I want to mention two other things: First, the unrecognized advantages of rock-in/rock-out magazines. While straight-insert magazines like those of an AR-15 allow for faster reloading in ideal conditions, the AK’s rock and roll arrangement allows for substantially greater leverage when removing and inserting magazines into the gun. This means that magazines are much less likely to get so stuck that the user cannot remove them (although it is obviously still possible, especially if magazines are used that do not fit the rifle).

Second, I want to note a small virtue of rifles – like the AK – that do not feature a last round automatic bolt hold open device. While I consider bolt hold opens to be a good idea, it is certainly worth mentioning that a rifle that does not have one will expose its action to debris for the minimum amount of time possible. In extreme conditions, such as sandstorms, the fact that the bolt group does not remain open during loading, allowing dust and debris to enter the action, may be a substantial boon to the rifle’s performance in these circumstances. Although, as I stated before, I consider last round bolt hold opens to be a good thing, the AK’s lack of one helps illustrate the kind of extreme compromises that might need to be made to achieve peerless reliability.

3. Ammunition and chamber design

It’s no secret that 7.62x39mm is one of the most designer-friendly centerfire rifle cartridges ever designed. Extremely well-tapered, with a wide bore and low thermal load, this rifle cartridge is optimized for reliable weapon function, not performance. Briefly, let’s take a closer look:

The 7.62x39mm’s successor, the 5.45x39mm, relaxes some of these features (specifically, smaller bore diameter, less ludicrous but still ample case taper), but still retains the thick rim, wide extractor groove, and considerable case taper.

No discussion about the AK’s chamber and ammunition would be complete without mentioning that the Kalashnikov was from the start an all-chromed gun, with chrome-lined chamber, barrel, piston and oprod, and in some models, even the entire bolt carrier. Chroming is essential in areas with high moisture levels (such as Russia in the summer, or Indochina), and a lack of it led to the greater part of the American M16 rifle’s problems during the first years of Vietnam. The fact that the most essential parts of Kalashnikovs were from the outset hard chromed no doubt contributed significantly to its reputation for dead nuts reliability.

4. Spring design

Perhaps the most overlooked basic element of firearms engineering are the humble springs. For modern “self-powered” (i.e., driven by the power of the round itself, as opposed to electrically driven) firearms, it is the springs that make the whole weapon possible. What we see with the AK’s springs is some of the most solid engineering there is to see in the world of modern automatic small arms.

The springs on an AK rifle are – each of them – designed to provide ample, even power throughout their strokes. This is done by ensuring the springs are never either fully compressed or fully extended during the normal operation of the firearm. The action spring of the AK, for example, does not quite compress completely, but instead the bolt group bottoms out against the rear of the receiver. This is bad for the rifle’s recoil characteristics, but good for the spring, letting it last longer without wearing out. Perhaps more importantly, though, then AK’s action spring never comes close to achieving its full extension, meaning that even when the bolt is completely locked and in battery the spring is still exerting a great deal of force against it. This means that in situations such as when the chamber is fouled, or the cartridge has been especially tough to strip from the magazine and eaten up a lot of the driving energy of the action, the bolt group will always have plenty of energy to close and lock. You can see the difference this makes at home, if you have examples of an AK and almost any other semi-automatic rifle handy: Load a round into each chamber and close the bolt, then pop the bolt open slightly. Many other weapons will stay out of battery like this, but an AK – provided its action spring is not worn out – will always close and lock even from a dead start with zero forward momentum.

The magazine springs give another good example of the dramatic over-engineering of the Kalashnikov spring system. Compared to its counterparts, the springs used in AK magazines are extremely long, meaning they too provide more consistent, constant force on the round stack, ensuring the first round rises quickly into position just the same as the last. Compared below is an AK-74 magazine on the left, and a Lancer AWM magazine on the right, with a USGI spring. Note that the AK-74’s spring is nearly twice as long!

Image source: Reader Brandon

This section wouldn’t be complete without mentioning the AK’s semi-famous braided hammer spring. A braided spring was a wise choice here, as the higher impact resistance of a braided spring allows for an even more violent (and therefore reliable) hammer action, ensuring ignition of even bombproof rifle primers. Like the rest of the springs in the rifle, the hammer spring too is never allowed to reach full extension or compression.

5. Fire control group design

Which brings us to the AK’s fire control group. In many ways, this is a study in orthodoxy, as the AK uses the same Browning double-hook trigger design that dates back to the old Auto-5 shotgun. However, coupled this this simple, reliable Browning trigger system is Kalashnikov’s own automatic sear and rate reducer, which not only allows fire control of all modes to occur from a single lever, but also reduces the automatic fire rate down to about 700 rounds per minute. You can see how this trigger group works in the video below:

Simpler automatic trigger groups have certainly been designed, but Kalashnikov’s is still an excellent design that builds on a proven, simple mechanism.

One final note about the fire control group is how the fire control chamber is designed. In an AR-15, the fire control group occupies a small space, with very little room for additional debris. In the unlikely event that grit does reach the fire control group, there is very little space for it to go but into the mechanism itself. However, AKs have a much roomier fire control housing that makes them substantially more resistant to invading debris and grit. They are, like any mechanical device, not immune to debris ingress, but the additional space substantially lessens the chance of malfunction versus other designs that have tightly packed trigger groups. It also, as a final point, makes this area substantially easier for the user to clean without disassembling it.

6. The Details

We will conclude by covering some of the small details about the AK that readers might not have considered as lending to its reliability. One of the major design drivers for Kalashnikov must have been performance in cold conditions (it is unthinkable that this wasn’t, given the Russian climate), and we see a number of features that appear to be compromises to this end. The large and much-lamented safety switch, which slows and loudens making the rifle ready to fire, is in freezing conditions a boon. The switch’s long length gives the user substantial leverage to break it free of ice, snow, and mud, where the short, convenient safety lever of another rifle might simply be frozen up entirely.

Finally, let’s not forget the simple effectiveness of a fixed, right-side charging handle. For most people, their dominant arm (most often the right) is the stronger of the two; this is perhaps one reason why bolt actions have their bolt handles on the dominant side, rather than the non-dominant. So, while the right-hand reciprocating charging handle of an AK is not the most ideal setup for 3-gun gaming, it is perhaps the ideal set up for malfunction clearance and troubleshooting, especially in bad weather. It should not be forgotten than just as important as – if not more than! – how infrequently a rifle has a problem is how easy it is to clear that problem and get the rifle back into action. Charging handle placement is perhaps too subjective to draw a clear conclusion here, but I encourage my readers at home to try this: Take your rifle, assuming it has a charging handle on one side or the other, and try charging it with the butt against your thigh. Then, flip it upside down so that the handle faces the other way, and try it that way with the opposite hand. Which did you feel was better? Why? Please, let me know in the comments!

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He can be reached via email at nathaniel.f@staff.thefirearmblog.com.

The second arc shouldn’t be as tall as the first; the AK handguard setup and rear sight base assembly are simply poor design features. Everything forward of the barrel trunnion is far less clever than the stuff behind it.

iksnilol

Sights attached to the barrel isn’t stupid IMO.

Non-free floating handguard is a bit stupid tho.

But it’s smart with the muzzle device.

ostiariusalpha

The muzzle device attachment on the AK is pretty nifty.

Twilight sparkle

The fact that they chose to use left hand threads so that to rifling twist won’t pull off the muzzle device even if the pin fails is cool. I’ve seen two golani sporters have their birdcage fall off because they chose to not use left hand threads

ARCNA442

I think free-float handguards on what was basically a submachine gun would have been a rather unnecessary expense.

However, I do wonder why they didn’t extend the wooden handguards out to the gas block.

Tritro29

That’s not a design failure, it’s an industrial and logistics one. When you need cash for like 20000 tanks, having some “poor” design choices isn’t very bad, especially as the rifle designed is over-perfoming. You guys should be forced to take a strategic planning course when reading about Military Weapons, that would cool off most of you into understanding why the AK became what it is.

BrandonAKsALot

Considering how long ago it was designed, I’d say they did alright. I agree with iksnilol, the rear sight on the barrel is very logical. You want sights on or as close to directly attached to the barrel as possible. The hand guards wee comparable to anything else designed right around those times. Hell, even M16s weren’t free floated. That’s kind of a more recent thing.

Regardless of who is responsible for its design, these articles are great summaries of precisely why the AK is so reliable. Thanks.

Pete Sheppard

Rob Ski has repeatedly made an interesting point about AK/AR field reliability, after Ian’s mud bath tests; the AR is harder to foul to failure, but the AK is much easier to clean and return to service. As a US Army infantryman, he knows a few things about mud and crud.

gunsandrockets

I’ve always liked the Mini-14 for how easy it is to clean, and been annoyed at the AR for how inconvenient it is. That buttoned up design which so isolates the AR interior from outside contamination, also makes it harder to clean all its nooks and crannies.

iksnilol

Yeh, but Mini-14 is a bit too open.

AC97

Like the M14 before it.

It’s easy as hell to stop either of the two with dirt, sand, or mud.

gunsandrockets

One thing I’ve wondered about is whether that open design also facilitates the dumping of waste heat compared to the closed-up AR-15.

I’ve been struck by some histories I’ve read where overheating problems of a firearm were more readily solved by getting rid of insulating elements rather than increasing the barrel weight.

Gary Kirk

You talking about the action, or the accuracy??

iksnilol

Both… definitely both.

The Mini-14 I saw wasn’t fired much but it patterned like a decent shotgun… with an open choke.

Pete Sheppard

My Kel-Tec SU16, with its enclosed receiver and ‘star’ bolt, is also a pain to clean around the chamber

ExMachina1

I don’t know. That’s sounds more like a “that’s not a flaw, that’s a feature” kind of hedge. The InRange mud tests showed that the AKs fouled easily, but I sure didn’t see an easy combat fix short of hosing it out.

Pete Sheppard

I’m pretty sure that’s Rob’s point. In one video, he takes an AK he fouled with sand, pulls the bolt carrier and swishes it in a creek to clean it out. He pointed out that an AR is much harder to clean out.

Isaac Newton

Perhaps worth mentioning is the fixed ejector that allows less moving parts a ejector springs. As a bonus the ejector also acts to help guide the bolt when not being pressed into the dip in the cam track.

Amplified Heat

Also gives far, far more extraction force for a gun that cycles as hard as the AK (and eliminates the force an ejector button applies that cants/binds a case against the side of the action during extraction, and requires much less force to seat the rim in battery for a push-feed style bolt face like the AR/AK). The aggressive extraction is probably why it’s so important the AK has such a beefy rim, however (that said, even HK roller guns don’t typically rip rims off 223 cases)

Isaac Newton

Add to that, lower cost and complexity make the stamped and welded stationary ejector a good design choice vs an ejector, retaining pin, and spring in the bolt.

Green Hell

I want to personaly thank you, Nathaniel, for those articles, it’s nice to finally see someone in the west to apretiate the deep thought and and engeneering that is put into the development of Russian weapons, witch are usually considered “crude and symplyfied” by all the wrong reasons.

Riot

The reliability aspects outside an automatics operating mechanism are always underestimated.
3 things that could of improved the armalite rifles without overhauling design are: More case taper, better springs (these go for almost everything) and someone slapping stoner when he proposed that mag well cause its way too friggin deep!

Also me see MAS, me happy.

Amplified Heat

Also using the T-handle as the backup charging handle scheme instead of a forward-mounted handle design, after the vertical trigger in the carry handle was canned. By far the biggest design flaw in an otherwise excellent product.

gunsandrockets

The AR-15 magwell seems pretty good for the original type 20 round sized magazine. Doesn’t the problem really begin with the larger 30 rounders?

iksnilol

And drums in general.

Riot

The magwell dictates the magazine design, this should never be the case. It is true 20 round mags have less issues, but the problems would not have come up with a good initial design.
Another issue with the depth is the amount of surface area – the image Nathaniel posted shows it quite well since the lancer is patterned – if the mag got stuck like from the cold that’s a lot of area to stick and friction to overcome.

I have a suspicion that aesthetics are to do with the mag well layout.

Remember, the 20rd magazines were the standard issue magazines during the XM16E1 failures experienced in late-1966-early 1967.

Continuous curve 30rd magazines were trialed as early as 1965. Alas, Colt had not held the tolerances of the magazine well in check. As a result, these magazines would not fit in all issue rifles. Colt went back to the drawing board and came up with the basic profile that is still used today – straight at the top of the tube, and then curved below the magazine well.

gunsandrockets

A truly homely mag!

gunsandrockets

Since the original conception for the AR-15 magazine was to use 20 round disposable magazines rather like an M1 clip, the magwell of the AR-15 provides good protection for the fragile lightweight aluminum 20 rounder.

The Army even used to issue 20 round magazine bandoliers rather like an M1 clip bandolier. 7 magazines to one bandolier, and two full bandoliers would fold up to perfectly fit inside a 200 round 7.62mm ammo can.

IshTheBuddha

20 round mags have given me problems more often than not. Certainly more often than 30 round mags. And honestly, after firing magazine after magazine after magazine through an M4 all day, I truly came to appreciate that mag well. It makes shoving a new magazine into the rifle when you are tired, shooter fatigued, and wearing gloves an extremely simple, mindless task.

I do agree that the mag well is indeed aesthetically pleasing. The MK47 mutant looks hideous to me.

ostiariusalpha

More case taper is nice, but largely unnecessary for brass ammunition. There are a variety of aftermarket spring and spring-like designs that supposedly improve performance over the mil-spec ones, take your pick if you feel adventurous. That deep magwell is part of the sealing of the AR design that keeps crap out of the action, it is more well thought out than you might realize.

Real engineering improvements to the AR rifle and ammunition would look more at the extraction part of the cycle, with a thicker rim for the 5.56x45mm than the pistol case type rim it ended up with, and a wider extraction groove to enable a larger extractor claw. With a barrel extension that’s 1/10th of an inch greater in diameter than the AR-15 extension, you’d be able to use a slightly larger, more rugged bolt that has the larger claw which would improve extraction greatly. A larger bolt body would have few breakages at the cam pin hole also. Other than that, the AR could definitely do with an enlarged FCG area, not just for handling internal debris, but also making room for a better burst fire design than the flawed 3-round mechanism that they crammed into that tight space.

I don’t think there’s a need for burst fire at this point, so I disagree with you on that, but otherwise I think you are correct.

ostiariusalpha

Perhaps not, but if your going to get stuck with a burst fire mechanism by the higher ups, then it might as well be one that resets and doesn’t change your trigger pull; all of which is easier to fit in a roomier FCG well.

Doesn’t seem like the higher ups these days care much about burst mechs.

ostiariusalpha

And thank goodness for that. This was more a look back at how the rifle could have been improved at the outset, not how it should be altered in the future. I’d prefer a wholly new rifle with new ammunition designs at this point.

Reed Jaracz

These two articles are absolutely my favorites out of everything I’ve read on this site. Detailed, but clear and concise, focusing on facts and explanations rather than opinion, conjecture, and unfortunately repeated factoids.

More in-depth, detailed articles are coming in the future, I hope.

MPWS

This is certainly good writeup which goes well into detail – and it cannot be in any other way. I suppose, with some effort we could go even further, such as relationship of chamber/ cartridge dimensions, headspace tolerance range and so on.

One thing which we unfortunately cannot avoid is instant comparison with AR. If we managed to avoid it, it would help in better evaluation; but this is natural tendency of many including myself.

Paul Epstein

Agreed- maybe it should be compared the vast plethora of other assault rifle designs, many of which are failures *because* of their poor reliability. The AR is widely agreed to be reliable enough for people to have trusted their lives with it for fifty years, and a lot of rifles definitely can’t say that.

The FAMAS, as one example- the delayed blowback action, as cool as I think it is, is very sensitive to even small changes in ammunition characteristics, and if it gets slowed down at all extraction can become pretty much impossible for the rifle on it’s own.

SlowJoeCrow

Yes, it would be interesting to see how the AK compares against an FAL with sand cuts or a G3 since both have a good reputation for reliability and were widely used.

tiger

count me in the non Ak & non AR fan club.

Wolfgar

This write up matches your outstanding right up on the M-1 Garand,. I new about the pre- engagement but never gave it much thought till now. Your video was great help in understanding it. Like you, my appreciation for the Kalashnikov rifle has grown with age. Just a suggestion, you should look into creating a book on your many reviews and write ups. It would be much better than the same old rehashed trivia that is out there. Well done, two thumbs up!

Wolfgar

The only question I have is about the rate reducer. Kalashnikov himself stated it was not to reduce the rate of fire but an anti bounce device. Opinion?

I imagine if Kalashnikov contradicts me on something regarding his rifle, you should listen to him, not me. 😉

I do believe it does reduce the rate of fire, however.

Wolfgar

In addition, a hammer retarder was added to prevent the weapon from
firing out of battery (without the bolt being fully closed), during
rapid or automatic fire.[37]
This is also sometimes referred to as a “cyclic rate reducer”, or
simply “rate reducer”, as it also has the effect of reducing the number
of rounds fired per minute during automatic fire.

This was some of the detail written.

Joseph Goins

Nice try, Nathaniel! You didn’t prove that “it [is] the most reliable automatic rifle in the world!” (your closing line yesterday), but you did your best.

Green Hell

What is than? Never heard a proper answer from anyone saying it isn’t.

Joseph Goins

To say “”it [is] the most reliable automatic rifle in the world” would require one to examine every “automatic rifle” design that exists “in the world.” Nathaniel’s writing was a far cry from that. (A lot of what was said today cannot possibly prove his thesis even if he meant “it is one of the more reliable automatic rifles in the world.”)

ozzallos .

You’ll just have to accept ‘most reliable gun he’s ever handled’ as the take-away prize then, which is what most people really mean when writing these sort of articles.

Joseph Goins

“You’ll just have to accept ‘most reliable gun he’s ever handled’ as the take-away prize then”

That — “most reliable gun he’s ever handled” — is believable and more realistic. However, it is still not supported by the information provided.

“which is what most people really mean when writing these sort of articles.”

While that may be true, that isn’t what he said. He said: “Fear not, though, tomorrow we will be back, examining the rest of the Kalashnikov’s best features which make it the most reliable automatic rifle in the world!” There is no qualifier to that statement. (The statement is also false because it assumes that the rifle is the sum of it’s individual parts as opposed to their collective operation, but that is a topic for a different day.)

“Regarding the title, I might as well say it here: It’s a matter of fact that I need an eye-catching title that’s not too long. So I could write “one of the most reliable semiautomatic rifles in the world” but it’s shorter and better to write “the most reliable rifle in the world”.

“And of course, I want people to tune in for part 2, so I close with that as well.

“I know this level of showbiz pisses some people off (not you, but some people), but I’m not writing a technical document for the government. I have a challenge in that I need to get people to actually read my writing to appreciate it, so I don’t really have the luxury of calling it “A TREATISE ON THE RELIABILITY ENHANCING DETAIL FEATURES OF THE KALASHNIKOV RIFLE”. ;)”

And here’s the thing: I know from having written over a thousand articles in two years that even if I did make the title and closing statement Nyquil-boring, someone would accuse me of clickbait.

User

Why dont you just then write “6 Reasons the AK47 might be the most reliable Rifle in the world”.
(And AKM might make more sence than “AK47”)

That way you dont make up facts, are not outragesly clickbaiting, and make yourself a lot more credible, than the way its titled now.

I don’t know why you think I should use “AKM”. “AK-47” has some fierce brand recognition so it’s the obvious choice.

The job of the title is to get your attention, not to be an ironclad statement of fact. It is my opinion that overall the AK is arguably the most reliable production rifle in the world, so I don’t feel like the title is as off base as you seem to.

Wolfgar

User, please read this so you wont be confused any longer.

Receiver development

File:AKMS and AK-47 DD-ST-85-01270.jpg

AKMS with a Type 4B receiver (top), and an AK-47 with a Type 2A

There were many difficulties during the initial phase of production. The first production models had stamped sheet metal receivers. Difficulties were encountered in welding the guide and ejector rails, causing high rejection rates.[37]
Instead of halting production, a heavy machined receiver was
substituted for the sheet metal receiver. This was a more costly
process, but the use of machined receivers accelerated production as
tooling and labor for the earlier Mosin–Nagant
rifle’s machined receiver were easily adapted. Partly because of these
problems, the Soviets were not able to distribute large numbers of the
new rifle to soldiers until 1956. During this time, production of the
interim SKS rifle continued.[37]

Once manufacturing difficulties had been overcome, a redesigned version designated the AKM (M for “modernized” or “upgraded”; in Russian: Автомат Калашникова Модернизированный [Avtomat Kalashnikova Modernizirovanniy]) was introduced in 1959.[38] This new model used a stamped sheet metal receiver and featured a slanted muzzle brake on the end of the barrel to compensate for muzzle rise
under recoil. In addition, a hammer retarder was added to prevent the
weapon from firing out of battery (without the bolt being fully closed),
during rapid or automatic fire.[37]
This is also sometimes referred to as a “cyclic rate reducer”, or
simply “rate reducer”, as it also has the effect of reducing the number
of rounds fired per minute during automatic fire. It was also roughly
one-third lighter than the previous model.[38]

Both licensed and unlicensed production of the Kalashnikov
weapons abroad were almost exclusively of the AKM variant, partially due
to the much easier production of the stamped receiver. This model is
the most commonly encountered, having been produced in much greater
quantities. All rifles based on the Kalashnikov design are frequently
referred to as AK-47s in the West, although this is only correct when
applied to rifles based on the original three receiver types.[39]
In most former Eastern Bloc countries, the weapon is known simply as
the “Kalashnikov” or “AK”. The photo above at right illustrates the
differences between the Type 2 milled receiver and the Type 4 stamped,
including the use of rivets rather than welds on the stamped receiver,
as well as the placement of a small dimple above the magazine well for
stabilization of the magazine.

Receiver type

Description

Type 1A/B

Original stamped receiver for AK-47. -1B modified for underfolding
stock. A large hole is present on each side to accommodate the hardware
for the underfolding stock.

(this naming convention continues with all types)

Type 2A/B

Milled from steel forging.

Type 3A/B

“Final” version of the milled receiver, from steel bar stock. The most ubiquitous example of the milled-receiver AK-47.

Type 4A/B

Stamped AKM receiver. Overall, the most-used design in the construction of the AK-series rifles.

In 1974, the Soviets began replacing their AK-47 and AKM rifles with a newer design, the AK-74, which uses 5.45×39mm ammunition. This new rifle and cartridge had only started to be manufactured in Eastern European nations when the Soviet Union collapsed, drastically slowing production of the AK-74 and other weapons of the former Soviet bloc.

Cal S.

Arguably the Israeli Galil.

gunsandrockets

Re: cartridge design

It always seemed to my eye the 7.62mm NATO cartridge also had features intended to improve function in semi-automatic/automatic weapons, such as larger extractor groove and beefier rim, in addition to subtle shaping of the rim edge to assist typical extractors to smoothly snap over the rim. The contrast to a Mauser rifle cartridge case head stands out upon comparison.

I believe the first rifle cartridge adapted that deliberately incorporated some of those same features is the French 7.5mm cartridge. Which makes perfect sense since it was first used in the Mdl 24/29 7.5mm LMG. I think it was a parallel French development of cartridge and LMG?

Cartridge case taper is a two edged sword. Steep taper also interferes with feed inside a large box magazine.

The 7.5 French is one of the first rimless rounds to be designed for light automatic weapons, and it’s striking how similar its rim and groove dimensions are to 7.62×39.

7.62 NATO was also designed with this in mind, but madeserious compromises in case taper to achieve the maximum internal olume for it’s 2.8″ overall length.

gunsandrockets

The 7.62x39mm case taper also makes the SKS chargers very clumsy to use. I’ve always had much better luck by downloading them to 8 cartridges each.

gunsandrockets

Re: rock-in magazine

Aside from what was mentioned, another aid to reliability seems to be the tighter magazine lockup tolerance in the pitch axis compared to an AR style magwell. Pitch angle is highly critical to magazine feed reliability.

gunsandrockets

Re: bolt hold open

For highly portable automatic weapons, I can see the sense in not only no bolt hold open but also closed-bolt automatic fire to aid reliability. For a weapon which is likely to see a large amount of movement in ground hugging postures, debris from the field is more likely to cause stoppages than overheating.

The exception to this rule would be top-feed bottom-ejecting automatic weapons like the Owen SMG and BREN LMG. Making gravity your ally instead of enemy is a good thing.

gunsandrockets

Pity the TRW ‘low maintenance rifle’ never saw service. Could it have beat the AK in reliability? Guess we will never know.

I’ve always wanted to handle an LMR. Would love to study that design in depth.

Minuteman

Outstanding write up Nathaniel! Plenty eye openers. Mikhail Timofeevich was an obvious genious. He got it all right and made the AK the way he made it for good reason. Everything about the gun’s details makes perfect sense. Although the sights and hand guard setup leave much to be desired, we must keep in mind that this rifle was of course designed in the mid 40’s.

Grump

There’s nothing wrong with the AK irons, it’s just they chose to optimize them for fast and close shooting with both eyes open, not Camp Perry competitions.

Minuteman

True! They serve their intended purpose.

Gary Kirk

Not to mention apertures freezing over tend to reduce accuracy just a bit

MarcoPolo

There’s a typo in the last paragraph. AK’s use reciprocating charging handles the last time I checked.

Again the gaps in the receiver are TERRIBLE for reliability, expecally mud. And the savety that OPENS up the receiver even more when set to fire is just stupid….
As said this isnt the only point in reliability, but means that the title is overdramatic and rather senceless.
And still im wondering about “AK47” , the AKM is named AKM for a reason.

I am wondering why you are fixated on the AKM when the article is about the entire AK family (“AK-47” just has the best name recognition).

User

Thats EXACTLY my problem. I know your you need to make a living, no problem. But i expect MUCH more from you…
You call it the “THA MOST RELIABLE RIFLE OF THA WORLT”, not just that this title is bullshit for a credible writer, but that “AK47 has the best recognition”, is just stupid when you use such a dramatic and extremly SPECIFIC title.
Also do you really think we all are so stupid that we dont know the AKM? I mean who reads this articles? Not the kind of dumb casual people that the only weapon name they know is the “AK47”. Your just completly trowing away your (in my opinion verry high) crediblity.
That really worrys me.

My hope is that as many people as possible read my articles, as opposed to whatever crap is on BusinessInsider or WeAreTheMighty this week. While I take my commenters seriously, my audience is everyone who reads my articles, not just the ones who comment.

YZAS

Wow, that was an incredibly informative series there. I always wondered about the taper on x39. You definitely went way beyond the normal ‘piston-operated, built like a tank, loose tolerances’ generalization, and really broke it down in detail. As with any mechanism or system, it’s a zero sum game – so compromises are made based on the designated priorities. In the case of the AK, it’s all about reliability and durability, and Mikhail achieved that in spades.

UCSPanther

The long-stroke piston and rotary bolt has been incorporated into numerous other weapons as well. The SIG 540 and 550 series are good examples of that.

MPWS

Right, this one might be next in order of Nathaniel’s attention; at least I wish it was.

AC97

Forget about the AR-15 vs the AK-47, that argument is officially a horse that has been beaten to death and resurrected to be beaten again, what about the AK-47 vs the G3/roller-delayed blowback rifles in general?

Uniform223

The AR-15 vs AK realiability has been beaten to death so much it might as well be like Glen and Abraham at this point…

n0truscotsman

hahahahahaha!!!! You’re evil! 😉

Blackhawk

When comparing the reliability of two rifles using “intermediate”cartridges vs. rifles using “full power” cartridges (e.g. 7.62×39/5.56 vs 7.62×51 ) are you, or are you not comparing “apples and oranges?” I ask this, not being a smart-ass or having an opinion one way or another. It seems to me that the popularity of the intermediate cartridges (and the subsequent dominance of the AR/AK rifles) stemmed more from the exigencies of the jungle warfare which embroiled the US during the period of initial adoption of the M-16 – and the apparent tunnel-vision it engendered in that environment as opposed to the longer engagement ranges predominant in places like Europe or Korea. Perhaps if the US hadn’t been involved in Vietnam in the 60s and 70s, the battle rifle caliber weapons then in use would have been considered “adequate” in the West, and the G3/CETME designs might have become the dominant pattern for Western militaries. Or perhaps American dominance of NATO would have, instead, lead to the dominance of the M-14 designs – even with its flaws?

Patriot Gunner

HK made the HK33…essentially a G3 chambered 5.56…probably what AC97 was referring to.

AC97

Yep, that’s exactly what I meant by “and roller-delayed blowback rifles in general”.

BrandonAKsALot

Roller delay is well known for functioning extremely well within a small parameter. Once your ammo varies too much, it struggles. It’s simple in many senses, but has high wear on parts. As far as which would keep running under the most adverse conditions, I couldn’t tell you, but it would be interesting to see. The HK design was refined over a very long time starting with the Spanish original designs, so they work well.

MPWS

One item which had not been mentioned and which is crucial to reliability is stripping and feeding shot into chamber. If you look at functional diagram, you will notice how substantial is engagement of bolt with cartridge during initial contact. This is also important due to varying shot angle during process of feeding. Distance from front of magazine to mouth of chamber also helps in this objective. Compare with AR15 – huge difference!

I may have overlooked that. If so, my apology.
You have gone thru all important points, as far as I can tell.

A Fascist Corgi

One of the things that I never understood is why AKs that are chambered in 5.45×39 are supposedly more reliable than AKs chambered in 7.62×39. The Wikipedia page on the AK claims that the AK-74 was a lot more reliable than the AKM.

BrandonAKsALot

It’s likely less to do with caliber and more about the AK-74 itself. The 74 and then 74m had many small mechanical refinements that you wouldn’t notice unless you knew what to look for. The bolt and carrier were redesigned slightly along with many other parts and I’m guessing it may have been beneficial in reliability.

Dr. Longfellow Buchenrad

But the AR15 is the most reliable platform shooting the 5.56×45 NATO cartridge ever adopted by the US in the 1960s for general issue…

Ed

You got good points. Think AK-74 is better. 5.45mm better round than 7.62×39.

I’m sorry, that was rather mean-spirited. However, there are a number of problems I have with the article.

1) Actually more of a question to design heritage. Why do more people think that the STG44 was copied instead of the SKS?
2) Aside from the attempt to incorporate gas pistons, if the AK is such a world-beating design, why don’t more countries copy it for their rifles? Hard to believe it’s stuborness or politics alone.
3) If the AK is so reliable by nature, why is it so dependent upon the country of manufacture? Or, like everyone else says when the AR tops it in particular trials, are you only speaking of Russian manufactured AKs?
4) If the AK is such a reliable rifle, then why does the modern AR top it or tie it in so many categories?

3.) Because metallurgy and manufacturing methods matter, regardless of what rifle design we are talking about.

4.) Because they are both very reliable rifles. For an example of one area where the AK kicks the snot out of the AR-15, try cold weather performance.

Cal S.

1) You know how people say that the AK is a mod-cop of the STG44? It seems more likely to me that more people would say it was a mod-cop of the SKS. Why isn’t that the prevailing false impression? Ignorance of the SKS or desire to attribute it to the Germans?
2) Quite. Forgive my apparent ignorance, but what countries, aside from former Soviet-Blocs or counties with no R&D ability to take a set of calipers to copy what was sent them, operate MSRs that have a majority AK design heritage?

ostiariusalpha

What the heck, I can chime in too…

1) It’s because people are stoopid, and the AK externally looks more similar to the Sturmgewehr than it does to the SKS. Pretty much that simple. There’s the matter of the long piston stroke vs short piston stroke, but really the majority of confusion centers around superficial appearances.
2) The Israeli Galil and Finnish Valmet are basically copies, and the SIG rifles crib quite a lot from the AK.

Cal S.

1) To me that always seemed superficial. Before I knew what an SKS was, I just saw a funny-looking AK with a built-in bayonet at a gun show and thought it was an AK-variant. Never would have personally made the leap to the STG44.
2) Yes, the Galil is a much-improved version. However, the Tavor has been phasing it out and is set to replace it in 2018. With SIG, is that directly inspired or STG44 to AK kind of inspirational leap?

1) Because most narratives rely on emotion rather than facts, and nobody feels strongly about the SKS.

2) You may not be aware, but the AK is possibly the most cloned and adapted automatic rifle of all time. I am not going to list derivatives as that information is readily available through your search engine.

Cal S.

1) Indeed.

2) I agree, but a good portion of those are ex-Soviet-Bloc countries. I’m also not talking just a bolt here or a long-stroke gas piston there. I’m talking actual full-on mod-cops out there. I’m talking weapons like the Galil, RK-62, etc. Calling the AR-70 an AK-derivative is edging pretty close to calling the AK an STG 44 derivative just because of the bolt face. I agree, though, that a full list at this point is not necessary. However, I’d be willing to bet money that, in accordance with my original criteria of “have a majority AK design heritage” + “Not Soviet-Bloc”, the list would in fact be remarkably short.

guest

1) for the same reason people thing M1AX tanks are invincible on the battlefield
2) penile deficiency syndrome and/or political bias
3) because even when making a steel hammer with a wooden handle, one has to use mallable steel and not pot iron, same reason here
4) in what categories, where? this is like saying a F1 car tops a cargo van in every race. Sure, but when s*** needs to get done toys become useless

Cal S.

4) Huh, let’s see. I’ll tell you here, but you’ll have to do the digging just as I have. Don’t worry, it’s really easy.
A) Tops the AK in Mud (Re: InRangeTV)
B) Tops the AK in Longevity (Re: TFB article covering tabluated empirical data from Las Vegas MG range)
C) Ties the AK in Water
D) Ties the AK in Dry tests
E) Ties the AK in Sand tests* (unless you open it up and pour it into the trigger group, but now we’re just being ridiculous)

The AR-15 is no ‘toy’, and is presently, by all objective measures (i.e. not the AK forums), equal to the AK-47/74. It’s really like arguing whether the F-86 or MiG-15 was superior. Both performed well-enough, and each had strengths and weaknesses that offset each other. The AK’s is mud, the AR’s is cold temperatures (so I’ve heard).

*No one gives any real credence to the infamous 2007 Army Trials because 60% of those M4s were entirely out of spec before the test even began. Besides, it’s conjecture to surmise the AK’s performance because it was not included in the testing.

Elvis

“the AK’s rock and roll arrangement allows for substantially greater leverage when removing and inserting magazines into the gun. This means that magazines are much less likely to get so stuck that the user cannot remove them”

A rushed reload on an AK can sometimes lead to the front of the magazine not locking in, but the rear of the magazine does… when this happens, the magazine is locked in, the rifle won’t feed, and it’s a struggle to get the magazine unlocked so it can be re-inserted correctly.

So, my question is, ‘Much less likely to get stuck than what?’ I’ve never had this failure in any other weapon. I’ve had it in most, if not all, of my AKs.

How about those folks in the non AR/AK club? The FN/FAL & delayed roller lock H &K’s were in the same Cold War arms race.

ARCNA442

They also appear to have decidedly lost said arms race given their disappearance (and that of their descendants) from modern militaries.

Patriot Gunner

Nathan I think the fact that the AR 15 doesn’t have an “anti-preengagement” is blown out of proportion in your article because even still the AR 15 cycles a whole heck of a lot smoother and than any AK (especially with all the new coatings on the market). If we measured the force required to strip a cartridge from the magazine and properly insert it into the chamber the AR 15 would come up the clear winner against the AK. Even a top end AK, one from Rifle Dynamics or Krebs, still sounds like a rusted iron anchor being dragged across a gravel pit when it’s being charged. Only the new Galil Ace is the exception to this, and I wouldn’t even consider that gun an “AK” because it is so heavily modified and changed from your classic Russian style AK’s. And although I don’t disagree with most of the reasons you presented why the AK is a superior rifle in terms of reliability, its a moot point considering how open the design is. Many videos online (Forgotten Weapons, Tango Foxtrot, etc.) have proven that dirt inside the trigger area will cause the rifle to stop working pretty easily. So I ask what good is it if the system is not sealed against the elements? Who cares if it is easier to clean, I’d rather survive the battle with a reliable sealed gun and take it back to base to clean. Having a gun that is “easier” to clean is not a virtue of reliability.

In the video I said that not having APE isn’t that big of a deal, but that it’s something worth including if extremely high reliability is a major requirement.

Also, I don’t know why you think even well-built AKs don’t have smooth actions. My SLR-104FR is a pretty normal factory AK and it is much smoother than my AR-15, especially on a loaded mag.

Patriot Gunner

Yeah, but I would argue that it isn’t really required even if your after extremely high reliability. I mean your test in the embedded video wasn’t really fair, when the gun is assembled and every part is in working order, the spring pressure would easily overcome the pressure exerted by your finger on the bolt. Again, if extremely high reliability is a concern, POF roller cam, problem solved.

Lots of successful guns have been designed without APE mechanisms, but an APE mechanism gives you that much more margin for your springs and your bolt group. Having one means your springs can be that much less powerful, your bolt group that much lighter, and your bolt group velocity that much lower, because you don’t have to power through those frictional losses. Plus, there’s no risk of additional fouling magnifying the friction so badly that the gun stops running.

Patriot Gunner

If your gun is sealed you don’t have to contend with crap getting in ;). And carbon fouling actually lubricates the bolt carrier (one of Stoners brilliant ideas), and contrary to popular belief your AR doesn’t have to be white glove clean to run reliably. I know this is getting old, but I’ll refer you to the POF roller cam lol.

I get the impression that you haven’t run a firearm in harsh conditions for extended periods of time. Something that InRange-style videos don’t show you is that over time debris works its way into even the best sealed firearms, and will eventually cause them to stop working.

Also, seriously, did you watch my APE video above? It seems like you didn’t. I say so because, please, watch it and tell me if my AR-15 looks “white glove clean” to you.

Patriot Gunner

I am a friend to someone with a type 7 FFL with the class 3 SOT and a 50 acre plot…Yeah dude I’ve ran guns hard.

I did see your video, but to call that an “honest” assessment of the lack of APE in the AR is completely bogus. The upper was disassembled, had it actually been assembled (and all parts are in working order) the amount of force you exerted on the bolt would have done nothing.

I really don’t care about how dirty or clean your AR is…that statement was a generality.

I’m talking about shooting in sandstorms, in ice, and in other extreme weather. It’s very interesting what this teaches you, for example that “sealed” guns really aren’t, if they’re exposed to crap for long enough.

In what way was my upper receiver disassembled, because it didn’t have the charging handle in it? The charging handle does not interface with the cam pin and therefore has no effect.

Patriot Gunner

Yeah I agree with you on that, no gun is ever 100% sealed. But I still think that there is a degree to which a rifle must be sealed and every possible step must be taken to seal the vital parts. I look at the AK and think “dang, no effort at all was made to seal it”…Looks like we will just have to agree to disagree on this one as well.

Disassembled from the lower, no charging handle and under no spring pressure is what I meant.

Compromises must be made, like I said. You want a gun with a reciprocating charging handle and a cover that is less susceptible to ice and snow… Well, there you are.

Patriot Gunner

You keep saying compromises must be made, I get what your driving at, but there are several guns on the market that do have reciprocating charging handles however they are pretty well sealed. Scar and CZ 805 come to mind immediately. I don’t think its a compromise you have to make, not anymore anyway.

It doesn’t reduce the outward forces caused by the compression of the bolt and the bolt carrier, it just adds a bearing that reduces friction. Don’t get me wrong, I’m not saying it’s a bad solution, but a true APE mechanism is better.

Patriot Gunner

Oh come on Nathan. Your video was about friction and the POF roller cam solves it, Lantac also makes a very good (similar) solution. And you didn’t acknowledge any of my concerns in my original post ;). So I will re-state them here. If a gun is designed to be extremely reliable, shouldn’t it take into account elements and debris entering into it’s action and vital parts? I mean at the end of the day it doesn’t matter how much clearance you have if stuff is easily getting in there. I think a gun that would be sealed AND had generous clearances would be ideal, but still having one that is sealed vs one that isn’t is still preferred.

The AK is pretty well sealed, just not as well as an AR-15. There are also good reasons for some of the design decisions that make the AK a little more susceptible to mud, for example not burying the chamber inside of a barrel extension makes the chamber easier to inspect and troubleshoot if something goes wrong.

Roller cams have been around for a long time. They alleviate the problem, but not to the degree that an APE mechanism does. A roller reduces friction due to pre-engagement; a true APE mechanism eliminates it.

Patriot Gunner

“The AK is pretty well sealed…” Lol, dude seriously? It has the big slot for the charging handle to ride in, the vents in the gas tube, the big old button at the end of the dust cover that retains the recoil spring and an overall fit like a commie era yugo. The AK is a better gun if you want to shoot it under water, I’ll give you that!

I guess we’ll just have to agree to disagree on this one…You should write an article about which one is a better weapon for war, with regards to production.

The AR-15 is easier to produce, if you’ve got aluminum forging machines and high labor costs.

Yes, the AK is pretty well sealed. No, it’s not well-sealed if the safety is off, but an AR-15 isn’t well-sealed if the bolt is back, either. The point is that compromises must be made. The AK is a pretty well sealed gun given the compromises they had to make (you, uh, need a slot for the charging handle). It has a dust cover that protects the majority of its operating group, and when the bolt it closed it does a good job of protecting its essential bits. It’s obviously not perfect in this regard and – as previously mentioned – the AR-15 is better sealed.

Again, technical discussion, not a boxing match. I said the AR-15 is cheaper to produce if you have high labor costs and forging machines because it’s true, not to score points.

pbla4024

So if you measure force needed to move the bolt from rear to front position, what will be the value for AR and what for AK?

ostiariusalpha

Besides its better sealing, the AR creates a lot more positive pressure around the ejection port (part of its infamous “pooping where it eats” trait that gets ragged on frequently), which you can watch blast debris away from the action in slow motion videos. The Ljungman and MAS guns do this too, which goes a long way towards explaining why they are more reliable than the M14, despite that they are all exposed actions.

Also, what concerns did I not address from your original post? You say basically X things:

1. You think I blew the matter of APE out of proportion (I didn’t, not if you watch the video all the way through).

2. You think an AK has more friction in stripping a round than an AR does. This is highly dependent on what magazines you’re using, but also not really relevant to the matter of APE. It is also further a completely unsupported statement, and I’m not convinced that actual testing would prove it to be true.

3. You talk about the AK being susceptible to mud. OK? All rifles are. AKs are more susceptible to mud than ARs, but less than Garands and their derivatives. F2000s are even better sealed than AR-15s, does this make AR-15s terrible and bad? This is a tiny portion of what makes a gun “reliable”, and it’s important not to over-emphasize it.

4. “Who cares if a rifle is easier to clean?” Well, presumably anyone who has to clean it.

Patriot Gunner

Dang looks like a struck a nerve lol…..

You did blow the APE matter out of proportion, that “test” in your video was completely bogus…

Given my experience with both firearms I would disagree and venture to say that it would take more force for the AK to strip a round and chamber it than the AR…I guess we’ll just have to agree to disagree.

I never said the AK’s were terrible and bad, just that the level of “reliability” has been mythicized by the west. And these articles are prime examples.

With regards to reliability, how easy a gun is to clean is irrelevant. With the right tools the AR is pretty dang easy to clean, yes I know you can clean your AK with a garden hose, OK fine I’ll give you that.

Good stuff Nathaniel, appreciate the time you took to dig into the small and important details. It was certainly educational for me!

10x25mm

Braided wire is used in springs to provide internal damping (within the spring) and suppress spring surging. Spring surging is common in long, small diameter coiled springs and other types of springs which have long, unsupported elements.

When a spring’s natural frequency is less than 15 times the frequency of the motion the spring, a compression wave (or in this case a torsion wave) is created that
travels back and forth from one end to the other or creates a standing wave. This produces irregular forces at the spring’s reaction points which are out of synchronization with an automatic firearm’s cycling.

Mikhail Timofeyevich must have encountered irregular disconnection or hammer capture by the sear due to hammer spring surging. The hammer spring must have been returning the hammer too soon in some instances, and too slowly in other instances.

It is worth noting that braided wire springs were first employed in firearms by Dr.-Ing, Gruener in the MG.42.

BearSlayer338

I love AK’s but I love my SKS more,partially because the SKS was a my last gift from my father before he passed,but also for how it feels and the reliability. I’d argue that the SKS is just as or at least pretty darn close to how reliable the AK is,before my father passed the SKS onto to me he had put at least a case or case and a half of 7.62×39(1K-1.5K) without cleaning it,I have never seen the rifle jam once or even fail to feed or extract. Now I know that part of that might be because of the country it is from: Romania,I’ve heard their stuff is just as good as the Russians.

MPWS

Still one thought on “anti-pre-rotation device”; options. Take a look at AUG; extremely cunning without causing additional drag. There is spring-loaded telescoping plate which engages bolt lugs. Once bolt enters barrel extension, plate recoils and bolt is free to turn. Also, Ron Barrett did not do badly on M82.

Yeah, the AUG has a neat APE device, and the FS2000 has an interesting one as well.

BrandonAKsALot

Excellent articles. Always good to see others appreciate the level of detail in the Kalashnikov design. Even the amount of work involved in assembling and testing was crazy. It’s not as intense anymore thanks to modern technology, but there used to even be quality control testing in the mag catch. You can find a small punch mark on Russian AKMs showing they passed the factory hardness test.

DW

As an AK varient, SIG55x (x=1,2,3) used rubber gaskets to cover the charging handle slot, I wonder how well it keeps debris out.
Yes InrangeTV should totally throw a (preferably swiss) SG55x into the mud…FOR SCIENCE

Banned Dude 7.62

That gap on AK pushes the water out of the receiver and is a feature, not a bug.

ozzallos .

There’s also a running thread over on arfcom with the guys from Battlefield Las Vegas concerning extreme usage of the AR versus the AK. This is not necessarily the same as reliability, but the long and short as I remember it is that when an AK goes down, it goes down hard. All that movement of the action really stresses the frame over time, whereas the AR simply has the consumable parts replaced.

Tierlieb

“Unlike an AR-15, which has to push its rounds over a ramped barrel extension and into the chamber, the AK has virtually nothing in between the round and the chamber itself. ”

But it does! Dinzag Arms made quite a bit of money providing feeding ramps for the early Saiga and Molot conversions, so you could use them with original mags.

It does kinda-sorta work without, but you need a different mag design for reliability, which pushes the round out higher, which sadly means you need to shorten the feed lips (or you get occasional bolt overrides). Or you use single stack mags that feed from the middle.

That said, the ramp of the AK is much simpler and smaller than the huge two-ramp construct that the AR-15 uses. Hell, you could cut one from a water pipe of the right diameter for those old Saigas and it worked perfectly…

This is another awesome series. Made me appreciate my AK even more. Thanks Nathaniel!

guest

You forget to say that unlike the AR and similar weapons where retention of the magazine relies of a simple little mag catch and the grace of God, which is strangely enough almost a direct copy of StG-44 type mag catch.

The foremost problem with that is that if for some reason the rifle experience excessive pressure on the magazine upwards, “into” the rifle, the catch can be bent out of shape and cause FTF and/or proper retention of the magazine. Unlike that the AK has positive locking of the magazine in the front and locks with a latch on the back, fully preventing any movement (except sideways).
This is illustrated in for example Russian training where soldiers do push-ups against an AK standing on its magazine. Along with this, a standard procedure of small arms tests is dropping the rifle, including dropping it on the mag.

IshTheBuddha

I’ve supported myself on the magazine of my m16 and/or M4 while laying prone many, many times and never had a problem. A good number of those instances were while wearing armor vest and ammunition, so i was pretty heavy.

Wolfgar

The length of travel the bolt carrier travels is also another positive design quality. The BCG has a long travel, “especially compared to the AR” which increases it’s momentum when it stripping a cartridge from the magazine. It is so long it will accommodate the 308 cartridge with out problem.

Pseudo

Fantastic articles! I cannot stress how much stuff like this is my favorite kind of material put out on this site. Keep up the good work.

Jones2112

Very interesting, I learned a few things…

Slim934

You should do a series on the ar-15’s neat design characteristics. This is a really great series.

Including thoughts on improvements in the designs would be neat too.

The Heretic

I prefer the Kalashnikov over the ArmaLite/Stoner design due to its reliability, but I have to say that the ergos on the AK-47 suck. Especially the insertion of a magazine. I have seen vids of reps from the Russian factories flub a mag insert badly and I know from experience that it is easy to get it wrong.